Coffee filter



y 22, 1951 J. w. MYERS 2,553,717

COFFEE FILTER Filed July 18, 1946 Patented May 22, 1951 UNITED STATESPATENT OFFICE COFFEE FILTER Joseph W. Myers, Philadelphia, Pa., assignorto Proctor Electric Company, Philadelphia, Pa., a corporation ofPennsylvania Application July 18, 1946, Serial No. 684,457

1 Claim. 1

This invention relates to coffee filters and more particularly to anovel filter which is adapted for use in the well-known vacuum typecoffee maker.

The present invention is in the nature of a further embodiment ormodification of the invention disclosed and claimed in my priorapplication, Serial No. 610,238, filed August 11, 1945, now Patent No.2,472,955. In that application, there is disclosed and claimed a coffeefilter comprising a pair of disk-like members having provision forremovable attachment to one another, said members having misalignedopenings so as to provide filter passages between said members, andmeans for varying the spacing of said members so as to vary thefiltering speed and the clarity of the coffee beverage. Such device ishighly desirable and advantageous, as set forth in the said priorapplication, and it meets all of the normal requirements as to clarityof the filtered beverage. However, some persons desire a crystal-clearbeveragesuch as can be obtained only by filtering through a filter sheetor the like.

The principal object of the present invention is to provide a filter ofthe above-mentioned type, wherein provision is made for filteringthrough a filter sheet, whenever desired, so as togive a crystal-clearbeverage.

Another object of the invention is to provide a filter of theabove-mentioned type, which is adapted to be used alone and which givesa very satisfactory degree of clarity of the beverage when thus used,and which is also adapted to employ a filter sheet whenever the userdesires an extreme degree of clarity of the beverage.

A further object of the invention is to provide a novel filter devicewhich is easy to keep clean and does not deteriorate with age, and whichis adapted to employ a sheet of material that may serve as a filterwhenever the user desires a crystal-clear beverage.

Other objects and features of the invention will be apparent as thedescription proceeds.

In the accompanying drawing,

Fig. 1 is a small scale view, partly in section and partly in elevation,of a vacuum type coifee maker with the novel filter of the presentinvention disposed therein;

Fig. 2 is a perspective view of the coffee filter;

Fig. 3 is an exploded view showing the detachable parts or members ofthe filter in perspective;

Fig. 4 is a fragmentary sectional view, on a relatively large scale,showing the filter members positioned for use with a filter sheet, andshowing such sheet in p a Fig. 5 is a similar view of the device,showing the parts positioned for use Without the filter sheet; and

Fig. 6 is a perspective View showing the filter sheet removed from thedevice.

Referring first to Fig. 1, the vacuum type coffee maker shown comprisesthe usual water heating vessel I and the coffee infusion vessel 2 withits lid 3. The vessel 2 has the usual tubular portion I extendingdownward into the vessel I and adapted to conduct liquid between the twovessels. In operation of this type of coffee maker, the water 5 invessel I is heated and rises upward in the tube 4 into vessel 2 where itcomes in contact with the ground coffee 6, the resulting infusion of theheated water and the ground coffee producing the coffee beverage. Whensubstantially all of the heated water has risen into vessel 2, theapplied heat is cut oil, and the vacuum created within the vessel Idraws the coffee beverage downward, into vessel I. It is necessary, ofcourse, to provide a filter device to prevent the ground coffee frompassing downward into the vessel I, and the present inven tion providesa novel filter device designated generally by reference character I. Thefilter device is adapted to seat in the lower part of vessel 2, and itmay be held securely therein by means of a spring member 8, one end ofwhich is extended and is adapted to hook over the bottom of the tubularportion 4, as shown at 9. A sealing member I!) is provided between theupper part of the vessel I and the lower part of vessel 2, as iscustomary in this type of coffee maker.

Referring now to the other figures of the drawing, the filter deviceprovided by the present invention comprises a pair of members I I and I2which are generally of disk-like form and which are provided witharcuate openings I3 and M of narrow width. Member I2 has a peripheralrim I5 formed thereon, within which member I I is adapted to seat whenthe two members are attached together, as shown in Figs. 4 and 5. Theopenings I3 and M are offset radially so as to provide filter passagesbetween the faces of said members when they are closely disposed.Preferably the openings are tapered as illustrated.

Preferably the members II and I2 are formed of non-metallic material,such as Bakelite, and a handle I6 of similar material is secured to themember I2 in the manner shown in Figs. 4 and 5. In the lower part of thehandle I6, there is provided a metal insert II which is recessed andthreaded at I8, and which projects through the central hub portion I9 ofmember II. The

- insert ll, and is threaded at 23, so as to engage the threaded portionE8 of the insert H. The stud 22 is also threaded at 24 to receive a nut25. The spring member 8, hereinbefore men-- tioned, has one end securedto the bottom of member 12 by means of the threaded stud 22 and nut 25,as shown in Figs. 4 and 5. The faces 1 of members H and 12, which areadapted to be brought into close adjacency to one another, are flatexcept for the projections and recesses now to be described.

As clearly shown in Fig. 3, member H is provided with a plurality ofprojections 25, which are located near the center of the said memberadjacent the open end of insert i? into which the stud 22 is adapted toextend. Preferably, the members it and i2 are divided into six equalsectors which are occupied by the arcuate apertures i3 and Hi. Thusmember ll is divided into six sectors by the radial portions 27, whilemember 52 is similarly divided by radial portions 28. On the outer facesof the two members there are provided radial reinforcing ribs such asshown at 29 in Fig. 2. As shown in Fig. 3, there are three of theprojections 26 on member ll, which are substantially aligned withalternate ones of the radial portions 21.

Member i2 is centrally recessed and has three recesses 35 separated byradial extensions 3! of the flat face of said member. The recesses 35]are substantially aligned with alternate ones of the radial portions 28,while the extensions 3: are substantially aligned with the otheralternate portions 28. The recesses 36 are complementary to theprojections 28 on member ii, and are adapted to receive said projectionswhen the two members are relatively positioned in a certain manner.

Member 12 is also provided with outwardly located projections 32 whichare adapted to establish a close spacing of the two members when theprojections 26 are seated in recesses 39.

When projections 26 are not thus seated but engage the radial extensions3i, the said projections establish a relatively wide spacing of the twomembers due to the fact that said projections are of greater height ordepth than projections 32.

In order to effect the different spacings of the two members, provisionis made for indexing the members in diiTerent relative positions. Tothis end, member H is provided with two recesses 33 and 33a which arelocated at the outer ends of two adjacent radial portions 21', whilemember 12 is provided with projection 34 which is located at the outerend of one of the radial portions 28 and is adapted to seat in either ofthe recesses 33 and 330.. When the two members are so relativelypositioned that projection 34 is seated in recess 33, as shown in Fig.2, the projections 26 seat in recesses Bil-and the projections 3?. areeiieotive to establish a relatively close spacing of the two members.This is the condition for use of the filter device without a filtersheet, as hereinbefore mentioned,

and it gives rapid filtering, with all grinds and roasts of coffee,through the small passages formed by the radially staggered apertures l3and M, as shown in Fig. 5. To this end, the projections 32 may beseveral thousandths of an inch in depth. While such use of the filterdevice gives a satisfactory degree of clarity of the cofiee beverage formost users, it does not give a crystal-clear beverage which some personsdemand even at the expense of slow filtering action.

When the members II and I2 are so relatively positioned that projection34 seats in recess 33a, the projections 26 engage the radial extensions3! and establish a relatively wide spacing of the two members, as shownin Fig. 4. This is the condition for use of a filter sheet which isshown at 35 in Fig. 4.

The two conditions above described are designated by the words plain andpaper applied tojribs of member II opposite the recesses 33 and 33a, asmay be seen in Fig. 2. These designations indicate to the user theproper positioning or member H relative to member l2 for each condition.

In using the filter device without the filter sheet, the members H andi2 are brought into proper relation, with projection 34 seated in recess33 and with the stud 22 extending into the insert 17. The handle [6 isthen turned to rotate insert 17 and thus secure the members together asshown in Fig. 5. The filtering device is then placed within the uppervessel of the coffee maker, as shown in Fig. 1, member I2 being providedwith a sealing ring 35 (see Figs. 4 and 5), formed of rubber or thelike, so as to effect a good seal with the vessel 2. During theoperation of the coffee maker, the filter device permits the water torise into the upper vessel and it permits the coffee beverage to passdownward into the lower vessel.

When it is desired to use the device with a filter sheet, the sheet isfirst placed over the lower member l2 with the stud 22 projectingthrough the sheet. It will be noted that the upper end of stud 22 istapered or pointed so as to readily pierce the filter sheet. Oneadvantage of the device is that any piece of paper which is capable ofserving as a filter sheet may be used.

For example, an ordinary paper towel or paper napkin may be employed.After the sheet has been placed over member (2, member 1 l is placedabove the filter sheet, with recess 33a positioned to receive projection34. The two members are then secured together by rotating'the handle it,after which the excess portion of the filter sheet may be torn away. Asshown in Fig. 4, the filter sheet 35 is securely held at its centralportion by the projections 26 on member H and the cooperating radialextensions 3! onmember 12. At its peripheral portion, the sheet isgripped by the peripheral portion of member H and-the rim 15 of memberl2. Fig. 6 shows the filter sheet removed from the filter device.

With the device thus conditioned for fine filtering of the cofieebeverage by means of the filter sheet, the faces of members H and I2 arespaced sufiiciently far apart to permit free flow of the beverage to theupper surface of the filter sheet. During the codes making operation,the water passes upward through the filter sheet, and the codes beveragepasses downward therethrough after the infusion has taken place;Afterjm. cofiee making operation hasbeen completed, the

members II and I2 are separated and the filter sheet is removed anddiscarded.

Whether the device is used with or without the filter sheet, the partsof the device may be readily cleaned by detaching them and by allowingwater to run through the apertures and over the faces of each part.Moreover, the device is durable and does not require periodicreplacement.

While a preferred form of the filter device has been illustrated anddescribed, it will be apparent that the device may be variouslymodified, particularly as to structural details. It is to be understood,therefore, that the invention is not limited to the specific form shown,but is commensurate in scope with the appended claim.

I claim:

A coffee filter adapted for use with or without a filter sheet,comprising a pair of circular disklike members removably attachedtogether at their centers, said members being relatively rotatable abouttheir centers and having confronting faces, said members being similarlydivided radially into a plurality of equal sectors each having arcuateapertures therein, the apertures of tial number of small filter passagesbetween the mutually adjacent solid areas of the respective confrontingfaces, and centrally located mutually cooperative projections andrecesses on said members inoperative when the members are in said onerelative position but operative when the members are in the otherrelative position to establish a relatively wide spacing of said facessuificient to accommodate a filter sheet between said faces and topermit free fiow of the cofiee beverage to the filter sheet, one of saidmembers having a peripheral rim within which the other member seats andwhich serves to clamp the filter sheet, said sheet being held at itscentral portion by the last-mentioned projections.

JOSEPH W. MYERS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 158,120 Porter Dec. 22, 18741,201,268 Davis Oct. 17, 1916 1,703,266 Dowling Feb. 26, 1929 1,885,850Marter Nov. 1, 1932 2,069,939 Browning Feb. 9, 1937 2,240,721 SelitzkyMay 6, 1941 2,472,955 Myers June 14, 1949 FOREIGN PATENTS Number CountryDate 9,643 Great Britain 1914 295,812 Great Britain 1928

